Mysterious wrist watch



Sep .23,1958 c. STERN Em 2,852,908

MYSTERIOUS WRIST WATCH 4 Filed Oct. :50, 1955 4 Sheets-Shet 1 Dmv awn-01s (lair/e5 57?? loll/1s Cuff-l r Sept. 23, 1958 c. STERN ETAL 2,852,908

MYSTERIOUS WRIST WATCH Filed Oct. 30, 1953 4 Sheets-Sheet z F1679 62 1 FIG. 10

JMVCYVI'OYS CAarles Sf'grn Low! F fher av- W Sept. 23, 1958 c. STERN ETAL 2,852,908

MYSTERIOUS WRIST WATCH Filed Oct. 50, 1955 4 Sheets-Sheet 4 J 'HVCRHI'S (Er/es .S'f'ern Louis I Co H'I'er MYSTERKOUS WRIST WATCH I Charles Stern and Louis Cottier, Geneva, Switzerland Application October 30, 1953, Serial No. 389,336

Claims priority, application Switzerland January 23, 1953 18 Claims. (Cl. 58-57) way of a mere exemplification various embodiments of the object of our invention. In said drawings: v

Fig. 1 is a plan view of a wristwatch according to ,our invention; a

.Fig. 2 is a plan view of the timing mechanism on an.

enlarged scale; 1 Fig. 3 is a cross-section through line LIL- III ofFig. 2; Fig. 4 is a cross-section through line IV-I V of Fig. 2; Fig. 5 is a cross-sectional view of a detail on an en larged scale; 7 a V Fig. 6 is a perspective view of the plate carrying the timing mechanism;

second embodiment of the wristwatch; v

Fig. 8 is an axial cross-section through line VIlI --Vlll ofFig. 7;

Figs. 9, and 10 are cross-sectional. views of two modifications;

Fig. 11 is a plan view of a square wrist watch;

Fig. 12 is a plan view of the timing mechanism of .last,

mentioned watch on an enlarged scale, and

Fig. 13 is a cross-section, through line X'll-IXlll of i Fig. 12, on an enlarged scale.

The timing mechanism of the Watch illustrated in Figs. 1 to 6 includes a circular plate 1 provided with two lugs la' andllb located under the terminal sections 2 of the watch case. The barrel spring motor or spring box 3 is located centrally of the plate and extends substantially throughout the surface of the timing mechanism. The

periphery of the barrel spring motor is' provided with a series of teeth 4 engaging the pinion 5 forming part of "the first movable gear of the time train, said pinion being rigid with the wheel shown at ,6. The finishing or time train includes two further movable gears 7 and '8 driving the escape wheel 9; the balance wheel is shown at 10. The finishing or time train and the regulating parts are located partly on the central part 1 of the plate and partly on its lug 1b; the speed-reducing ratioof the.

finishing or time train is selected in amanner such that the spring-box executes one revolution in twelve hours. The cover 11 of the spring-box extends outwardly into. a peripheral annular con-cave section 11a carryinga toothed ring 12. Said toothed ring carries inwardly directed elastic tongues 13 secured by screws 14 (Fig. 5) and engaging elasticallythe peripheral section 11a of the.

cover 11 so as to produce a frictionalengagement he- Fig. 7 is a plan view of the timing'mechanism in a third embodiment, to wit a Patented Sept. 23, 1958 tween said cover and the ring 12. A transparent disc 15 carrying a mark 16 forming an hour-indicating element is fitted inside an inner peripheral notch of the ring 12. The plate 1 is provided with an annular upstanding cylindrical flange 10 provided with gaps in register with the lugs la and 1b. Two arcuate members 17 provided each with two inner projections 17a are secured to said flange 10 through the agency of screws 18. Said projections 17a engage an outer annular groove 19 formed in the upper section of a toothed wheel 20 inside an inner peripheral notch of which is fitted a transparent disc 21 carrying a minute-indicating mark 22 (Figs. 2 and 5).

The teeth on the ring 12 mesh with a pinion 23 forming part of the first movable gear of the motion work and rigid with a wheel 24 controlling a second movable gear 2526 controlling in its turn a third movable gear 2728 meshing with the teeth on the ring All. These three movable gears are carried by the lug 1a on the plate. The friction between the toothed ring 12 and the cover 11 of the barrel allowssetting the watch right as provided by a knob 29 (Fig. l) and a transmission gear which has not been illustrated.

Between the two transparent discs 15 and 21 is fitted a suitably cut-out dial 30 carrying the scale of hours. Said dial is fitted inside a recess 31 formed at the inner periphery of the flange 1c rigid with the plate 1 and it is secured therein by means of screws 32 (Fig. 5).

is located underneath the plate" 1; said ratchet wheel is controlled by the abovementioned knob 29 through a windingupmechanism thathas'not been illustrated. The

-' which assumes, when seen. from above, a concave shape,

watch described is o'f'the so-called mysterious type since the hour and minute marksld and 22 are shown as suspended in space and wholly disconnected; as the spring box is very thin, the appearance is asif the cover 11,

were forming the bottom of the Watch case.

The upstandingflange 1c of the plate 1 may plate; the lugs 1a and 1b of the plate may also be omitted.

Similarly, the discs of transparent material 15 and 21 may be omitted, inwhich case the time-indicating marks 1 carried thereby would be replaced by corresponding hands understanding the invention have been illustrated, and a complementary section 37; The section 35-36 forms an ordinary timing mechanism of conventional type; of: which some details have been modified. These modifications consist in the elimination of thecan'non pinion and of the hour-wheel. These parts are replaced by a wheel 38 frictionally mounted on' a stud 39 rigidwith the springbox cover 59 and meshing with a wheel 40 fitted over a short tubular spindle-41a rigid Witha concave disc 41 coaxial with the timingrnechanism. A bridge-piece 42,

secured to the plate 35 by means of screws 58, a fitted be tween the wheel 41) and the disc-41. The wheel 40 is provided with an annular raised projection 49a revolving Said inside an opening provided in said bridge piece. bridge piece 42 serves also as .a bearing for one-end of the spindle 43 of the eccentric barrel spring motor. The

concave disc 41 revolves at the speed of. one revolution per twelve hours and carries anhour-indicating:member or mark 44. Said disc is outwardly, toothed as shown at 45.

be re placed by one or. more bridge'rnembers fitted over the The plate 35 is surrounded by antouter. annulus 46 to s g which is secured aring 48 by means of screws 47. Said ring is provided with lugs 49 which are held in position by the screws 47 and which extend radially towards the inside of the watch. Said lugs carry the outer periphery of an outwardly toothed ring 50, which is provided with a mark 51 forming the minute-indicating part. The con nection between the disc 41 and the ring is ensured by three movable gears 5253-54 forming the actual motion-work. The teeth 45 on the disc 41 drive the pinion of the gear 52, while the wheel of the gear 54 drives the toothed wheel 50. Said toothed wheel 5-0 is held in position by elastic members 55 that are also secured by the screws 47. The timing mechanism includes, furthermore, an annular dial 56 provided with an opaque part 56a and with a cut-out part 56b carrying the scale of hours and underneath which the indicating parts 44 and 51 progress. The central opening of the dial allows the concave surface of the disc 41 to be seen, which surface appears to the observer as forming the bottom of the watch case.

For setting the watch right, an ordinary arrangement is used which includes a sliding pinion and a draw member, the time-setting transmission 57 meshing with the wheel 40. By reason of the friction between the wheel 38 and the stud 39 on the barrel spring motor or springbox, the latter is not driven by the time-setting operation.

In the modification iillustrated in Fig. 9, the concave disc 60 carrying the hour-indicating member, is fitted over the hour-wheel socket 61. The latter is revolubly carried by the cannon wheel 62 fitted over the spindle 63 of the movable gear 64 forming the great wheel, the pinion of which gear is driven by the barrel spring motor 65. The cannon wheel 62 is shorter than in usual watches so that it does not extend beyond the socket 61a rigid with the hour wheel. The concave disc 60 rests through its outer periphery on an annular bearing 66 formed on the ring 67 carried by the annulus 46 surrounding same. The disc 60 is prevented from rising by elastic tongues 68 secured to the ring 67 by means of screws 69. A ring 50 is mounted above the disc 60 and is held in position like the ring work that is not illustrated and that is identical with the motion-work 525354 of the preceding'embodiment, ensures the connection between the ring 50 and the disc 60, which latter revolves at the rate of one revolution per hour. The watch also includes a further motion-work 70 which forms the usual motion-work connecting the cannon pinion with the hour wheel and cooperates with the means adapted to time the watch and which have not been illustrated.

In the modification illustrated in Fig. 10, the barrel spring motor 65 drives a movable gear 64 or great wheel forming part of the time train. The spindle 63 of said movable gear 64 carries no cannon pinion and no hour wheel. A stationary ring 71 surrounding the timing mechanism carries at a point of its periphery a spindle 72 to one end of which is secured a pinion 73 driven by the going barrel 65. Said spindle 72 carries at its other end a pinion 74 frictionally fitted over the lantern pinion 75 meshing with a transmission gear 76 revolubly carried by a ring 77 secured to the ring 71. Said pinion 76 meshes with the teeth on a concave disc 78 revolving at the rate of one revolution per twelve hours. Said disc 78 drives in its turn, through the agency of a motionwork similar to the motion-work 5253-54 referred to hereinabove, a ring 50 revolving at the rate of one revolution per hour. The disc 78 is carried at its periphery by means that are not illustrated and are similar for instance to those carrying the disc 60 in the modification shown in Fig. 9.

The arrangement for setting the watch right, which ar- 50 in the case of Figs. 7 and 8. A motionsquare case 79 in which the timing mechanism is fitted through the agency of an enclosing frame 89 the outer periphery of which is square and the inner opening of which is circular. The barrel spring motor 81 is located centrally of the timing mechanism; its cover 82 assumes the shape of a concave disc and carries an outwardly toothed ring 83 frictionally mounted on the cover 82 through the agency of tongues 84. The barrel spring motor executes one revolution in twelve hours. The ring 83 carries an hour-indicating mark or reference 85. Said outwardly toothed ring 83 meshes with a gear 86 forming part of a motion-work including three transmission gears 868788 of which the latter drives an outwardly toothed ring 89. The latter rests on tongues 90 carried by a ring 91 secured to the enclosing frame by screws 92. The toothed ring 89 revolves at the rate of one revolution per hour and carries inwardly a mark 93 forming the minute-indicating means.

The drum or outer wall of the barrel spring motor 81 is provided with a series of teeth 94 engaging the first movable gear 95 of the time train including the movable gears 95', 96, 97 and 98. The balance is shown at 99. The ring 91 carries an annular dial 1% which conceals the ring 89, while its square central opening allows seeing the time-indicating marks and 93. The latter project, in fact, inwardly from underneath the dial 100. The length of their visible section varies in accordance with their angular setting. There is thus obtained a so-called mysterious effect which is associated with the delusive appearance of the concave disc 82 which, when seen from above, seems to form the bottom of the watch case.

The central opening of the dial may assume any desired geometrical shape adapted to produce an ornamental effect. The annular dial may also be replaced by a rim extending above the ring 89 and concealing the latter.

What we claim is:

1. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the mechanism carrier plate, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel spring motor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, an hour indicating element carried by the upper surface of said concavedisc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last mentioned ring.

2. In a wrist watch, the combination of a timing mechanism, a plate carrying said timing mechanism, a barrel spring motor controlling said timing mechanism and carried coaxially by the plate, an upwardly concave disc extending over the timing mechanism in register with at least the major part of the surface of said plate, said barrel spring motor driving said concave disc at the rate of one revolution per twelve hours, an annular series of teeth arranged at the outer periphery of the disc, soft friction means through which said barrel spring motor drives said series of teeth, a transparent disc provided with an hour indicating mark and fitted inside said frictionally driven series of teeth, a motion work driven by said teeth, an outwardly toothed ring arranged coaxially above the disc and driven by the motion Work, and a minute indicating element carried by the last mentioned ring.

3. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in register with at least the major part of the surface of the carrier plate, said barrel spring motor driving said concave disc at the rate of one revolution per twelve hours, an hour-indicating element carried by said concave disc and extending above same, an outwardly toothed ring mounted over said concave disc, elastic tongues secured to the toothed ring and frictionally engaging the underside of the concave disc to urge the latter yieldingly against said ring to make the latter move in unison with the disc, a motion Work driven by said teeth, an outwardly toothed ring arranged coaxially above the disc and driven by the motion work, and a minute indicating element carried by the last mentioned ring.

4. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in register with at least the major part of the surface of the carrier plate, said barrel spring motor driving said concave disc at the rate of one revolution per twelve hours, an hour-indicating element carried by said concave disc and extending above same, an annular series of teeth arranged at the outer periphery of the disc, soft friction means through which said barrel spring motor drives said series of teeth, a motion work driven by said teeth, an outwardly toothed ring arranged coaxially above the disc and driven by thecarried by the plate, a barrel spring motor controlling,

said timing mechanism and carried -by the plate, an upwardly concave disc extending over the timing mechanism in register with at least the major part of the surface of i the latter, said barrel spring. motor driving said concave disc at the rate of one revolution per twelve hours, an hour-indicating element carried by said concave disc and extending above same, an annular series of teeth arranged atthe outer periphery of the disc, soft friction means through which said barrel spring motordrivessaid series of teeth, a motion work driven by said teeth, an outwardly toothed ring arranged coaxially above the disc and driven by the motion work, a minute indicating element carried by the last mentioned ring, and a time train operatively connected with the outer periphery of .the barrel spring motor and carried at least partly by the second lug.

6. In a wrist watch, the combination of a timingmechanism, a carrier plate therefor, abarrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery. of the disc, slip friction means whereby the barrel spring motor makes said'teeth on the concave disc revolve at the rate of one revolution per twelve hours, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last-mentioned ring.

7. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensiverelationship withat least the major part of the surface ofthe plate, an annular series of teeth at the" outer periphery of the disc, slip friction means whereby the barrel spring motor'makes said concave disc revolve at the rate of one revolution per twelve hours, said fric tion means including a toothed wheel rotating in unison with the concave disc and a further wheel driving lastmentioned wheel and carried coaxially by the upper surface of the barrel spring motor, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last-mentioned ring.

8. In a wrist Watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel spring motor makes said concave disc revolve at the rate of one revolution per twelve hours, said friction means including a toothed wheel rotating in unison with the concave disc and a further wheel driving last-mentioned wheel and carried coaxially by the upper surface of the barrel spring motor to be frictionally driven by the latter, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged f coaxially above the disc and driven by said motion work,

and a minute indicating element carried by last-mentioned ring.

9, In a wrist watch, the combination of a timing mech-' anism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coexten sive relationship withat least the major part of the surface ofthe plate ec'centrically with reference to the barrel spring motor, an annular series of teeth at the outeripe-Q rip'hery of the disc, slip'friction means whereby the barrek spring motor makessaid teeth on the concave disc re-f volve at the rate of "one revolution per twelve hours, said friction means including a downwardly directed tubularl projection coaxially rigid with the underside of the con cave disc, a' toothed wheel-fitted over said projection,'a further wheel driving last-mentioned Wheel and a ffrictional connection between the barrel spring motor and said further wheel,- an hour indicating element carried by", the'upper surface'of said concave disc, a motion work" driven by the teeth on said disc, an ou twardlytoothed ring arranged coaxially above the disc and driven by said motion work, andarninute indicating element carried'by, last-mentioned ring. g

10. In a wrist watch, the'combination of a' timing mechanism, a carrier plate therefor, a barrel springmotor'c on trolling said timing'mechanism, an upwardly concave disc extending over'the timing mechanism in coaxial coexten-.

sive'relationship with at least the major part of the surface,

of the" plate eccentrically with reference to the barrel I spring motor, an annular series of teeth at the outer periphery of thedisc, slip friction means whereby the barrel spring motormakes said teeth on the concave disc,

revolve at the rate of one revolution per twelve hours, said friction means including a downwardly directedtubu:

lar projection coaxially rigid with theunderside of the concave disc, a toothed wheel having an inner peripheral, tubular section fitted over said projection, afurther wheel driving last-mentioned wheel and a frictional connection between the barrel spr'ingmotor and said further wheel, a bridge member secured to the plate of the timing mechanism and extending between the concave disc and'the first toothed wheel'associated therewith and provided with an opening surrounding the: tubular section in said toothed,

ring;

311. In a wrist watch, the combination of atirning mechanism, a carrierdplatetherefor, abarrel spring motor con-, ,1

7 trolling said timing mechanism, including a barrel spindle and carried by the plate of the timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel spring motor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, said friction means including a downwardly directed tubular projection coaxially rigid with the underside of the concave disc, a toothed wheel having an inner peripheral tubular section fitted over said projection, a further wheel driving last-mentioned wheel and a frictional connection between the barrel spring motor and said further wheel, a bridge member secured to the plate of the timing mechanism and extending between the concave disc and the first toothed wheel asso ciated therewith and provided with an opening surrounding the tubular section in said toothed wheel, and with an aperture for revolubly carrying the barrel spindle, 811 hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last-mentioned ring.

12. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring. motor, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel spring motor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, said friction means including a toothed wheel rotating in unison with the disc and a further toothed wheel driving'last-mentioned wheel, carried coaxially by the upper surface of the barrel spring motor and frictionally driven by the latter, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, a minute indicating element carried by lastmentioned ring, and a gear meshing with the toothed wheel rotating in unison with the concave disc and adapted to set the watch to time.

13. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate, an hour wheel rigid with the concave disc, a cannon pinion driven by the barrel spring motor and revolubly carrying the hour wheel, a motion work operatively connecting the cannon pinion With the hour wheel, an hour indicating element carried by the upper surface of said concave disc, a series of teeth at the outer periphery of said disc, an auxiliary motion work driven by said series of teeth, an outwardly toothed ring arranged coaxially above the disc and controlled by said auxiliary motion work and a minute indicating element carried by last-mentioned ring.

14. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, and upwardly concave disc extending over the timing mechanism, and in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery of the disc, a short cannon pinion driven by the barrel spring motor and located coaxially underneath the concave disc, an hour wheel revolubly carried by the cannon pinion, a motion work operatively connecting the cannon pinion with the hour wheel, a tubular projection depending coaxially from the lower surface of the concave disc and fitted over the hour wheel to rotate in unison therewith, means rigid with the plate carrying the concave disc and over which the latter is adapted to revolve, an hour indicating element carried by the upper surface of said concave disc, an auxiliary motion work driven by the teeth on said disc, an outwardly i toothed ring'arranged coaxially above the disc and driven by said auxiliary motion Work, and a minute indicating element carried by last-mentioned ring.

15. In a wrist Watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery of the said disc, slip friction means whereby the barrel spring motor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, said friction means including an hour wheel rigid with the concave disc, a cannon pinion driven by the barrel spring motor and revolubly carrying the hour wheel and a motion work operatively connecting the cannon pinion with the hour wheel, an hour indicating element carried by the upper surface of said concave disc, an auxiliary motion work driven by the disc, an outwardly toothed ring arranged coaxially above the disc and driven by said auxiliary motion work, a minute indicating element carried by last-mentioned ring and a gear cooperating with the first-mentioned motion work connecting the hour wheel with the cannon pinion and adapted to set the watch to time.

16. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel spring motor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, said friction means including a gear located peripherally with reference to the timing mechanism and driven by the barrel spring motor, a further pinion driven by last-mentioned gear and meshing with the teeth on the concave disc, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last-mentioned ring.

17. In a wrist watch, the combination of a timing mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate eccentrically with reference to the barrel spring motor, an annular series of teeth at the outer periphery of the disc, slip friction means whereby the barrel springtmotor makes said teeth on the concave disc revolve at the rate of one revolution per twelve hours, said friction means including a gear located peripherally with reference to the timing mechanism and driven by the barrel spring motor, a further pinion frictionally driven by last-mentioned gear and meshing with the teeth on the concave disc, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxialy above the disc and driven by the motion work, and a minute indicating element carried by last-mentioned ring.

18, In a wrist watch, the combination of a timing assayed mechanism, a carrier plate therefor, a barrel spring motor controlling said timing mechanism, an upwardly concave disc extending over the timing mechanism in coaxial coextensive relationship with at least the major part of the surface of the plate, an annular series of teeth at the outer periphery of the disc, and forming a ring, elastic tongues secured to the toothed ring and engaging frictionally the underside of the concave disc to urge the latter yieldingly against the ring and to make the latter move in unison with the disc, gearing means whereby the 10 barrel spring motor makes said upwardly concave disc revolve at the rate of one revolution per twelve hours, an hour indicating element carried by the upper surface of said concave disc, a motion work driven by the teeth on said disc, an outwardly toothed ring arranged coaxially above the disc and driven by said motion work, and a minute indicating element carried by last-mentioned ring.

No references cited. 

